Tobacco smoking and other factors in relation to serum alpha-1-antitrypsin.

Serum levels of alpha-1-antitrypsin were measured by radial immunodiffusion, and phenotypes were determined by electrofocusing in acrylamide gel in 160 subjects who were used as controls in a case-control study of hepatocellular carcinoma (HCC). The results were studied in relation to age, sex, diagnostic category, tobacco smoking, consumption of alcoholic beverages, presence of hepatitis B surface antigen (HBsAg), and serum levels of alphafetoprotein (AFP) by modeling the data through multiple regression. There was no relation of serum alpha-1-antitrypsin values with sex, HBsAg, AFP, consumption of alcoholic beverages, and diagnostic category (p > 0.25). By contrast, there were statistically significant dose-dependent positive associations of serum alpha-1-antitrypsin with age and tobacco smoking (p < 0.01 in both instances). The positive association of serum alpha-1-antitrypsin with tobacco smoking and the previously reported excessive elevation of serum alpha-1-antitrypsin in hepatitis B-negative tobacco-related cases of HCC suggest that alpha-1-antitrypsin is intimately related to the pathogenetic process linking tobacco smoking to HCC.